The first thing I noticed upon installing Mavericks on my Mac mini is that mouse movement on my second monitor was suddenly choppy. Instead of the mouse cursor moving smoothly across the screen as it does on my primary display, it travels in a jerking motion on my USB-powered monitor that relies on a DisplayLink driver.

Updating to a beta version of the DisplayLink driver that supports Mavericks didn't change anything. It turns out I'm not alone—and my troubles are mild compared to those experienced by other users.

Some applications can show severe flickering on DisplayLink screens. Examples of applications that show this issue are Safari, QuickTime, and the App store.

Some applications can show corruption and/or missing contents while updating windows contents. Examples are Maps, iBooks, and the Dock.

Display arrangement is not kept when using 2 or more DisplayLink displays.

All screens black and unusable after unplugging a DisplayLink screen. This is caused by Apple's Window server crashing. This can be recovered by replugging the DisplayLink device.

On the Retina Macbook Pro, changing the layout to mirror logs the user out. Again, this is caused by Apple's Window server crashing.

These problems can't be fixed with a new DisplayLink driver, the company said. "DisplayLink uses standard Apple interfaces to integrate into OS X to add additional USB graphics displays and obtain screen updates. Unfortunately, there appear to be regressions in these interfaces in OS X 10.9 which are exposed when using DisplayLink screens. DisplayLink does not have workarounds to fix these issues and requires Apple to fix these problems in future 10.9 OS X updates."

The list of Mavericks-specific bugs could expand, but it probably won't get much more extensive. "This list covers the major issues that we believe users will find. The release note for [DisplayLink driver] v2.1 will cover all known issues," DisplayLink Senior Product Manager William Roose told Ars.

DisplayLink contacted Apple to make it aware of the bugs, but there's no word yet on when they might be fixed. We've e-mailed Apple ourselves, but we haven't heard back yet.

There is also a separate performance problem in DisplayLink's driver that can be fixed by DisplayLink itself. "The performance issue was due to the way our driver has to register with the OS for resources in 10.9 and will be a problem with v2.0 and 2.1 beta," Roose told us. The stable DisplayLink 2.1 release, due out by Nov. 5, should reverse that performance decline.

As we noted earlier, the more severe problems described by DisplayLink must wait for a fix from Apple. (From what Roose told me, I think my choppy mouse movement is caused by the DisplayLink driver's own troubles rather than Apple's interface regressions.)

A repeat from Mountain Lion

DisplayLink's driver for Macs allows any Intel-based Mac to connect up to four monitors over USB. This isn't the first time a new version of OS X has resulted in trouble for some users.

In the case of Mountain Lion, some of the DisplayLink bugs existed until OS X 10.8.5, which came out more than a year after the initial Mountain Lion release. DisplayLink's support article for Mountain Lion shows that it can take a while to get everything right:

Kernel panic when using Bluetooth devices. Fixed by Apple in 10.8.1.

Screensaver may start running unexpectedly. Fixed by Apple in 10.8.2.

Kernel Panic on USB 3.0 with DL-3000 devices. Fixed by Apple in 10.8.2.

Safari browser crashing. Fixed by Apple in 10.8.2.

The login screen is missing. Fixed by Apple in 10.8.3.

Applications flickering on DisplayLink screens. Fixed by Apple in 10.8.3.

Finder or other applications can crash or not able to launch. Fixed by Apple in 10.8.3.

DisplayLink Audio not working on USB 3.0. Workaround is to use a USB 2.0 cable if audio is required. Fixed by Apple in 10.8.5.

Hopefully everything will get fixed a little quicker this time around.

Promoted Comments

Considering that Apple is touting "Multiple Displays" as a category that Mavericks improves upon, they should strongly considering not laying this issue on the back burner as they have in the past. Or perhaps they will just continue to encourage users to empty their bank accounts on a chain of thunderbolt displays?

You know, Apple has actually now laid some groundwork for their own USB display adapters.

The lightning display adapters for iOS work by sending a video stream hardware-compressed in realtime to an adapter that decodes them for display. AirPlay mirroring (and now AirPlay additional display support) in MacOS also works by sending a video stream hardware-compressed in realtime to an adapter that decodes them for display.

It seems like there's perhaps a new layer that these gadgets could hook into to improve support, or at least performance. Hm.

yeah, when apple with apple. here is a third party product than Apple seems really passionated to support (read: not at all)

If anything, it's a trifle surprising that they've been as "welcoming" as they have. This is the same Apple that deliberately disabled the OS-integrated disk-burning features on non-stock optical drives(back when Apple still cared about those) and. to this day, confines OS wifi management to Apple-shipped NICs exclusively (Sometimes you can sneak the right broadcomm card in there, if memory serves; but there is no API or interface that a 3rd party can target to get 'Airport' related stuff to work with their card.

I'm sure that the company whose silicon demonstrates that lousy performance over USB is good enough even for graphics, in many cases, is not going to be high on their list of 3rd parties to empathize with.

Yeah the USB adapter is a great cheap way to add a monitor to a Mac set-up. Updating to Mavericks broke my third monitor display - the top half of the display was frozen, and the bottom half would update but was glitchy and slow. Weird stuff.

Turning off "Displays have separate Spaces" in Mission Control made the USB-connected monitor properly functional again. Now working in Mavericks without a hitch. The pointer on the third monitor is still laggy, as you noted Jon.

My fix is adequate for my needs, but I hope Apple doesn't take forever to address this!

I see the draw of cheap/convenient USB external monitors, but we should all be able to agree that USB is a pretty "hack-ish" way of doing things. Those who live by the hack die by the hack, as I say. My employer gives them out and I am personally not a fan.

I see the draw of cheap/convenient USB external monitors, but we should all be able to agree that USB is a pretty "hack-ish" way of doing things. Those who live by the hack die by the hack, as I say. My employer gives them out and I am personally not a fan.

Aside from the retina line, the only viable option for 2 or more external displays on a Mac laptop is USB adapters or daisy chained thunderbolt monitors at $1k a pop.

How the hell do those things work anyway? USB 2.0 does not have nearly enough continuous bandwidth to support running a display at 60 or more frames per second, and even USB 3.0 would probably struggle as well unless the display is small. Do they use some lossy compression? Are there visible compression artifacts?

EDIT: I just did the math and apparently a 1366x768 display like the one linked in the article could theorically work over USB 2.0 without compression. Huh.

EDIT 2: No wait my math sucks, that sums up to about 240 megaBYTES per second. Definitely impossible under USB 2.0.

How the hell do those things work anyway? USB 2.0 does not have nearly enough continuous bandwidth to support running a display at 60 or more frames per second, and even USB 3.0 would probably struggle as well unless the display is small. Do they use some lossy compression? Are there visible compression artifacts?

EDIT: I just did the math and apparently a 1366x768 display like the one linked in the article could theorically work over USB 2.0 without compression. Huh.

For my part, I didn't even know this was an option to be totally honest. Apparently, I'm out in left field on this one.

Any word on bugs associated with connecting displays over HDMI adapters? I use a Rocketfish adapter to connect a second monitor over HDMI (through whatever port that is next to the USB ports). Looking forward to upgrading, but not if it breaks my second monitor...

We use them at my office - If a user needs 3 screens,, they need a USB adapter - Laptop + External on VGA or Display port + USB - ivy bridge laptop graphics can drive 2 displays, either the laptop + external or 2 externals. if you need the 3rd you need the USB unfortunately..

How the hell do those things work anyway? USB 2.0 does not have nearly enough continuous bandwidth to support running a display at 60 or more frames per second, and even USB 3.0 would probably struggle as well unless the display is small. Do they use some lossy compression? Are there visible compression artifacts?

EDIT: I just did the math and apparently a 1366x768 display like the one linked in the article could theorically work over USB 2.0 without compression. Huh.

EDIT 2: No wait my math sucks, that sums up to about 240 megaBYTES per second. Definitely impossible under USB 2.0.

I use a Toshiba Dynadock (USB 3.0) with my laptop, two external 1080p monitors connected. No problems whatsoever (in Windows). Displaylink uses compression and unless I'm watching full screen HD video on one of the external monitors (I don't) there are no artifacts.

Aside from the extra displays, the USB docking station also gives me headphone, mic, gigabit ethernet along with multiple USB 3.0 ports.

How the hell do those things work anyway? USB 2.0 does not have nearly enough continuous bandwidth to support running a display at 60 or more frames per second, and even USB 3.0 would probably struggle as well unless the display is small. Do they use some lossy compression? Are there visible compression artifacts?

EDIT: I just did the math and apparently a 1366x768 display like the one linked in the article could theorically work over USB 2.0 without compression. Huh.

EDIT 2: No wait my math sucks, that sums up to about 240 megaBYTES per second. Definitely impossible under USB 2.0.

I use a Toshiba Dynadock (USB 3.0) with my laptop, two external 1080p monitors connected. No problems whatsoever (in Windows). Displaylink uses compression and unless I'm watching full screen HD video on one of the external monitors (I don't) there are no artifacts.

Aside from the extra displays, the USB docking station also gives me headphone, mic, gigabit ethernet along with multiple USB 3.0 ports.

Of course, the thing has NEVER worked right in OS X.

So, does the monitor attached by USB have built in decompression at it's end? I imagine you can't just do a USB->DVI (with some sort of adapter) but it actually has to be a native USB interface on the monitor, right?

I have a dual monitor setup with 2 hp monitors on in each port of the mini and love the new dual monitor support (very very long overdue).

However, has anyone else noticed the wack-a-mole dock? If you have the dock with hiding turned on, sometimes it pops up on one display, sometimes on another, if there is a reasoning behind it, I haven't found it yet!

How the hell do those things work anyway? USB 2.0 does not have nearly enough continuous bandwidth to support running a display at 60 or more frames per second, and even USB 3.0 would probably struggle as well unless the display is small. Do they use some lossy compression? Are there visible compression artifacts?

EDIT: I just did the math and apparently a 1366x768 display like the one linked in the article could theorically work over USB 2.0 without compression. Huh.

EDIT 2: No wait my math sucks, that sums up to about 240 megaBYTES per second. Definitely impossible under USB 2.0.

Just guessing here but maybe it only sends the part of the screen that has actually changed. Most areas of a computer screen are pretty static outside of games and video.

Muhammed Tapdancing Allah, USB 1 and 2 are horrible shit. *ANY* goodness a single plug for mice, keyboards and printers it brought has been totally demolished by the pure Nazi/Stalin/Pol Pot levels of evil that are USB 2.0 hard drives and USB monitor adapters.

(looks over at file copy from one USB 2 hard drive to another on a brand new Mac mini.... 2TB... 12 hours remaining... FUUUUUUUUUU)

How the hell do those things work anyway? USB 2.0 does not have nearly enough continuous bandwidth to support running a display at 60 or more frames per second, and even USB 3.0 would probably struggle as well unless the display is small. Do they use some lossy compression? Are there visible compression artifacts?

EDIT: I just did the math and apparently a 1366x768 display like the one linked in the article could theorically work over USB 2.0 without compression. Huh.

EDIT 2: No wait my math sucks, that sums up to about 240 megaBYTES per second. Definitely impossible under USB 2.0.

I use a Toshiba Dynadock (USB 3.0) with my laptop, two external 1080p monitors connected. No problems whatsoever (in Windows). Displaylink uses compression and unless I'm watching full screen HD video on one of the external monitors (I don't) there are no artifacts.

Aside from the extra displays, the USB docking station also gives me headphone, mic, gigabit ethernet along with multiple USB 3.0 ports.

Of course, the thing has NEVER worked right in OS X.

So, does the monitor attached by USB have built in decompression at it's end? I imagine you can't just do a USB->DVI (with some sort of adapter) but it actually has to be a native USB interface on the monitor, right?

The monitors are connected to the docking station via HDMI and DVI, nothing special about them. There is hardware in the docking station that handles decompressing the output from Displaylink driver.

How the hell do those things work anyway? USB 2.0 does not have nearly enough continuous bandwidth to support running a display at 60 or more frames per second, and even USB 3.0 would probably struggle as well unless the display is small. Do they use some lossy compression? Are there visible compression artifacts?

EDIT: I just did the math and apparently a 1366x768 display like the one linked in the article could theorically work over USB 2.0 without compression. Huh.

EDIT 2: No wait my math sucks, that sums up to about 240 megaBYTES per second. Definitely impossible under USB 2.0.

Just guessing here but maybe it only sends the part of the screen that has actually changed. Most areas of a computer screen are pretty static outside of games and video.

You are correct. When most of the display content is static (as with a text based IDE), very little bandwidth is used.

Display over USB? That is a first for me too. Is it really cheaper than a D-sub+ Thunderbolt/mini DisplayPort adapter combo?

My USB 3.0 docking station was around $150, it has 1x HDMI, 1x DVI, mic, headphone, gigabit LAN and several USB ports.

I don't think I could get two monitors connected over a single displayport adapter. I don't have displayport on my windows laptop anyway. This setup works for both my macbook (used to anyway) and windows laptop.

Display over USB? That is a first for me too. Is it really cheaper than a D-sub+ Thunderbolt/mini DisplayPort adapter combo?

My USB 3.0 docking station was around $150, it has 1x HDMI, 1x DVI, mic, headphone, gigabit LAN and several USB ports.

I don't think I could get two monitors connected over a single displayport adapter. I don't have displayport on my windows laptop anyway. This setup works for both my macbook (used to anyway) and windows laptop.

Oh! I only just realised what you guys meant by it. I forgot about those docking stations.